Authors

Date of Completion

Embargo Period

Keywords

Major Advisor

Jun-Hong Cui

Co-Major Advisor

Zhijie Shi

Associate Advisor

Song Han

Associate Advisor

see above

Field of Study

Computer Science and Engineering

Degree

Doctor of Philosophy

Open Access

Campus Access

Abstract

Advances in underwater acoustic telemetry have paved the way for emerging technologies, such as underwater networked systems. Now underwater devices and sensors can interact with each other by forming wireless underwater acoustic networks. These devices are networked together through the use of acoustic communication. Although wireless networking is not a new idea, applying these principles to the underwater domain has become a novel and challenging problem. There are many reasons for these challenges but the two most important ones are the inherent properties of using acoustic signals for underwater communication and the development of large-scale underwater networked systems.

These new grand challenges have become the shaping factors behind the design of new system architectures, protocols and algorithms. Entire network protocol suites and testbed systems have been designed and are currently being used in the real-world for experimentation and evaluation purposes. However, the unique deployment environments of such systems allow for easier exploitation and as is usually the case, the security of said systems has not been considered. Further, the unique challenges posed by the use of underwater acoustics make existing security solutions unusable.

This dissertation work focuses on denial-of-service attacks and countermeasures for under-water acoustic networks and covers three major research thrusts, namely: 1) physical layer vulnerability; 2) network layer vulnerability; and 3) countermeasures.

We first investigate the vulnerability of the physical layer of underwater networks through use of jamming attacks. Jamming attacks inject malicious signals into the communication channel to corrupt or block legitimate communication from occurring. We define two types of attackers with four different attack methods. These attacks are evaluated on three commonly used underwater acoustic modems in a real-world experimental testbed in Mansfield Hollow Lake, Mansfield, Connecticut and in a lab testbed.

Secondly, we investigate the vulnerabilities of the network layer of underwater networks through use of spoofing or cheating attacks. We study commonly used pressure routing protocols and design a spoofing attack to observe the effects on network performance. A spoofing attack is where a node in the network sends out fake location information, claiming to be somewhere other than its actual location with intent to disrupt network operations.

Thirdly, we make use of the knowledge gained by our first two works to design a resilient pressure routing scheme for underwater acoustic networks, known as RPR. This protocol aims to maintain routing services in the presence of malicious adversaries. It utilizes cryptographic mechanisms, implicit acknowledgments (I-ACKS), geographic constraints and randomization to achieve its resilient packet delivery.